Variable authenticator



A ttorlley sept. 22, 1942. E. J. SHEEHY ET AL 2,296,312

VARIABLE AUTHENTICATOR Filed May l2, 1941 2 Sheets-Sheet 2 I nventorjinw/mp J. SHELL/g EDG/121,. TOTTE/v,

; Bf @www Aitomey atented Sept. 22, 1942 VARIABLE AUTHENTICATOR EdwardJ. Sheehy, New York, N. Y., and Edgar L. Totten, Hohokus, N. J.

Application' May 12. 1941, serial No. 393,140

3 Claims.

This invention relates to a variable authenticator, the general objectof the invention being to provide a mechanically variable and secretmeans for the authentication and verication of telegraphic. telephonicand mail communications, and the use of this device will safeguard theusers against fraudulent messages, tampering with or transmission errorsin the essential parts of messages.

The device can also be used in conjunction with a prearranged formula tocompose secret cipher messages and under certain conditions will effecta saving in the cost of telegraphic communications.

This invention also consists in certain other features of constructionand in the combination and arrangement of the several parts to behereinafter fully described, illustrated in the accompanying drawingsand specifically pointed out in the appended claims.

In describing the invention in detail, reference will be had to theaccompanying drawings wherein like characters denote like orcorresponding Figure 1 is a top plan View of the device.

Figure 2 is a fragmentary view of one of the belts used with the device.

Figure 3 is a section on the line 3-3 of Figure 1.

Figure 4 is a horizontal sectional view showing the interior parts.

Figure 5 is a section on the line 5--5 of Figure 1.

In these views the numeral I indicates a casing which preferably has itstop sloping down- Wardly from one end to the other and said top has anopening 2 therein. A shield member 3 extends across the upper portion ofthe casing at the small end thereof and a shield member 4 extends acrossthe high part of the casing, the opening being arranged between theseshield members. A sliding cover 5 covers the opening 2 and has its endoverlapping the members 3 and 4 and said cover is slidingly held inplace by a ange 6 at the top of the casing. The cover 5 is held inadjusted position by means of a springpressed detent l arranged in asmall housing 8 at the lower end of the cover, the detent engaging anyone of a row of holes 9 in the member 3.

The upper end of the cover is formed with a c'entrally located extensionIU which has a slot therein for exposing any one of the names of thedays of the Week as shown at I2 in Figure 1. these names being placed onthe member 4. By adjusting the cover downwardly or upwardly the desiredday of the week will be exposed through the opening. A window I3 isformed in the member 4 adjacent one end thereof and a second window |4is formed in the member 4 adjacent the other end thereof and suitableindicia is carried by the member 4 adjacent the windows and the slot asshown in Figure 1. The cover is also formed with elongated windows orslots |5, I6, and I8, the window being formed of two sections, the lower`section having adjacent thereto indicia giving the names of the monthswhile the upper section has adjacent thereto indicia indicating themoneys of various countries. The

other windows have the numerals and letters I adjacent thereto as shownin Figure 1 and above these windows and indicia are the words "Amounts,quantities, etc., Currency, Date and Alphabet also shown in Figure 1. Y

A shaft I9 extends across the casing adjacent its lower end and a pairof drums 20 are rotatably arranged thereon. A shaft 2| passes throughthe casing adjacent the large end thereof and one end of this shaftextends from the casing Where it is provided with a knob 22. A tubularshaft 23 telescopes the inner end of the shaft 2| and this tubular shafthas an end extending from the opposite side of the casing and hasattached thereto a knob 24. VA drum or roll 25 is fastened to the shaft2| while a similar drum or roll 26 is slidably but non-rotatablyconnected with the tubular shaft 23 by means of a key 21 tting in a slotin the drum 26.

Stop members 28 and 29 are arranged in the casing and prevent slidingmovement of the drum or roll 26. A clutch member 3D is carried by theinner part of the shaft 2| for engagement with a clutch member 3l,carried by the tubular shaft 23, the two clutch members engaging witheach other when the tubular shaft 23 is pushed inwardly by the knob 24.The clutch parts are held in engagement by the spring fingers 32.`engaging a groove 33 in the tubular shaft. However, a pull on the knob24 will cause the tubular shaft to move to the right in Figure 4 so thatthe spring fingers will move out of the groove.

Of course` it will be understood that when the clutch parts are inengagement the two drums or rolls 25 and 26 will be moved in unison wheneither one of the knobs,22 and 24 is turned but when the clutch partsare out of engagement then the drums 25 and 26 are individuallymoved bythe knobs 22 and 24. An endless belt or tape 35 passes over the drum 26and the drum or roll -20 which is in alignment with 4the drum or roll26, while a belt or tape 36 passes over the drum tape or belt has dataon the cover for each or roll 25 and the opposite drum or roll 20. Eachperforations therein and the drums 25 and 26 have projections 36adjacent their ends for engaging the perforations of the belts or tapes.

Each belt is provided with three rows of characters thereon as shown at31 in Figure 2, some of which will appear through the windows in thecover and others in the windows in the member (l.

The characters on the beltsmay be arranged as follows. The belt on theleft contains a column of consecutive numerals designated ascombination. or serial numbers reading from 01 to 99. Opposite are twoadditional columns of twofigure groups, each group being arbitrarilyplaced and each column of such groups arranged in three segments ofthirty-three groups, thereby separating any two-ligure group in thefirst column from any identical group in the second column by at leastthirty-three groups at any one setting of the combination numbers. Theright-hand belt also contains two columns of arbitarily placedtwo-figure groups staggered on the thirty-three group principle and tothe right,A an additional column of consecutive numerals designated ascombination numbers reading from 01 to 99.

The cover may be moved vertically a distance equal to six groups of thecolumnar belt figures and the longest of the windows in the cover willonly permit thirty-two groups of the columnar belt figures to be visibleat any one setting of the combination numbers. The data on the cover maybe engraved or written and may be numerals, amounts, quantities,dimensions, grades, types, etc., months, days of the week, alphabeticalsymbols or any other information deemed vital to the nature of thecommunications exchanged. The serial and combination ynumbers arevisible through the windows I3 and I4.

Each turn of either knob or the movement of the cover to any particularday of the week, results in a complete change of the columnar guregroups appearing at the windows in the cover in relation to the dataappearing on the cover opposite such groups, thus producing a differentarrangement of numerical values in relation to the serial number foreach day of the week and each setting of the combination numbers at thewindows I3 and IG.

The following will illustrate the application of the device in the caseof a New York bank authenticating a message going to their Washingtoncorrespondents:

Monday, January 3rd Message serial number 20. To Washington Bank. Chargeour account and pay Clarence A. OBrien (Signed) New York Bank. Eachdevice distributed by the New York bank is assigned two individual setsof combination numbers one set for messages to New York the other formessages from New York. Assuming that the combination is then turneduntil the first combination nurnber 01 appears in the left hand boxwindow and the right-hand knob turned until the second combinationnumber 01 appears in the righthand window. Both belts are thensynchronized at this setting by pushing in the right-hand knob andrevolved in unison until the serial number of the message, which is 20,appears in the lefthand window. An individual arrangement of numericalvalues in relation to the data on the cover is then ready to be appliedto the message quoted above.

The authenticating figure group or test is calculated by adding thenumerical values appearing in the windows opposite the data on the coverwhich correspond to the essential parts of the communication in thiscase being those underlined above.

Example Numerical Value January 68 3rd 48 1st letter of Clarence C 14Middle initial A 48 1st letter of OBrien fO 73 Currency U. S 81 200,00059 50,000 '70 6,000 52 500 87 30 99 2 63 (Decimals and fractionsdisregarded) Test '762 The serial number 20 is then joined to the test762 and inserted as the rst textword in the message, thus: 20762Chargeour account, etc.

On receipt of the message the Washington correspondent follows the sameprocedure as the New York operator, i. e., moves the cover to the day ofdispatch, which is Monday, and synchronizes both belts at "combinations01-01. The belts are then rotated in unison until the serial number,which is 20, appears in the left-hand box window. The numerical valuesin relation to the data on the cover are then identical to those used bythe New York operator and the reconciliation of the test proceeds asexplained above. Should the total differ from the test '762 it is anindication that any of the following may have occurred: (1) an error hasbeen made in transmission (2) miscalculation by the New York operator(3) contents has been tampered with or (4) the message is fraudulent.

By the use of this invention several thousand tapes or beltscontainingidentical figure groups may be made at one printing, yet bysetting the belts at the various combination numbers the equivalent ofalmost 10,000 completely separate and distinct variable authenticatorsare available.

Some present day printed authenticators provide a list of variablenumbers to be added to the test on communications in the order in whichthey are sent, and no provision is made in the message itself toindicate to the receiver which of such numbers are employed. In otherwords, they are merely hidden numbers added to the sum of the xednumerical values.

This would not be an objectionable feature should all the messagesarrive in their proper sequence. However, they do not, due to severalcensorship, where such is imposed. It frequently occurs that messagesemploying this method of authenticating are received as much as tennumbers are out of sequence and it remains purely a matter of guessworkas to which of the variable numbers to apply to any particular message.Should an error in transmission occur in the test number, or the amount,the variable number selected might coincidentally verify the error, andresult in the wrong amount being paid.

Due to the uncertainty of such an arrangement any message arriving outof sequence could not be safely acted upon untilI the sequence had beenput into proper order and under present conditions this would frequentlymean that several days accumulation of messages would exist before allthe messages could be safely authenticated.

By using this invention however the serial" number of the messageautomatically controls the arrangement of numerical values to be applied to each message and the sequence in which the serial numbersarrive is then of no importance.

Furthermore, ordinary printed authenticators in use today are usually inthe form of a printed folder containing data similar to the cover ofthis invention but having fixed and permanent numerical values. One ofthese folders might easily be extracted from the files of an institutionand its absence, in the case of an inactive correspondent, would not bediscovered perhaps for several days.

By the use ofv this invention the possibility of the above would beeliminated as the device would be used for both active and inactivecorrespondents and must therefore be available continuously.

Inasmuch as present day authenticators contain the same numerical valuesfor all.holders and some only differ between holders by one numericalvalue, the test produced by such authenticators is subject to breakdownby any of the several holders since only one group of figures isnecessary to complete the "test and this group may be ascertainedthrough the process of elimination. Whereas, with this `invention eachholder has two secret combination numbers permitting a differentarrangement of numerical values for each of 99 messages for each of thesix days of the week in one direction, and a similar variation in theopposite direction. With the vinclusion of the dates of the month andthe names of the months on the cover, a message instructing the paymentof an amount of say $1,000 could be made to the same beneciary 99 timesa day and would always be authenticated by a different group of test"figures until the same day of the week occurred again on the same day ofthe month which usually happens about every six years. From this it isapparent that with such a vast number of variations, a breakdown of thetest figure group produced by this invention would be most difcult ifnot impossible.

This invention can be used for numerous purposes, such as theverification of formulas, measurements, parts of machinery, colors,sizes and lengths of lumber, grades of commodities, and in fact anyinformation transmitted by telegraph, telephone or mail where it isimportant to guard against mistakes and where the authenticity of themessage `must be assured.

It is thought from the foregoing description that the advantages andnovel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction andin the combination and arrangement of the several parts provided thatsuch changes fall Within the scope of the appended claims.

Having described the claimed as new is:

1. In a device of the class described, a casing having an opening in itstop, a sliding cover on the top of the casing covering the opening,means for holding the cover in adjusted position, a shield at the top ofthe casing having data thereon and the upper part of the cover having awindow therein for displaying this data, windows in the shield adjacentthe sides of the casing, longitudinally extending windows in the coverand indicia on the cover opposite the windows, a pair of rolls in thelower part of the casing, a pair of drums in the top part of the casing,belts carrying indicia passing over the drums and rolls, means forrotating the drums to bring the indicia on the belts into view at thewindows in the cover and in the windows in the top member and meanswhereby the drums can be rotated individually or together.-

2. In a device of the class described, a` casing, a pair of axiallyaligned drums in one end of the casing, a shaft passing through a sideof the casing and to which one drum is connected, a tubular shaftpassing through the opposite side of the casing and to which the otherdrum is slidably but non-rotatably connected, the tubular shafttelescoping the other shaft and clutch means for detachably connectingthe two shafts together when one shaft is moved inwardly.

3. A structure as recited in claim 1, wherein invention, what is thesliding cover is moved in a step-by-step motion for setting uppredetermined combinations of data. on the shield and indicia on thecover and belts.

EDWARD J. SHEEHY. EDGAR -L. TOTTEN.

